/* Copyright (c) 2015 - 2017, Nordic Semiconductor ASA
 *
 * All rights reserved.
 *
 * Use in source and binary forms, redistribution in binary form only, with
 * or without modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
 *    conditions and the following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 2. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * 3. This software, with or without modification, must only be used with a Nordic
 *    Semiconductor ASA integrated circuit.
 *
 * 4. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 *
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

import path from 'path';
import fs from 'fs';
import {
    logger,
    setAppDirs,
    getUserDataDir,
    getAppLogDir,
} from 'pc-nrfconnect-shared';

import { mkdirIfNotExists } from '../main/mkdir';

/**
 * Load an app from the given directory dynamically.
 *
 * @param {string} appDir the directory of the app to load.
 * @returns {Object} The loaded app object.
 */
const loadApp = appDir => {
    const moduleManifest = path.join(appDir, 'package.json');

    if (!fs.existsSync(moduleManifest)) {
        console.log(
            `Trying to load module, but package.json is missing in ${appDir}.`
        );
        return null;
    }

    // Using window.require instead of require, so that webpack
    // ignores it when bundling core
    return window.require(appDir);
};

const ensureDirExists = async dir => {
    try {
        await mkdirIfNotExists(dir);
    } catch {
        throw new Error(`Failed to create '${dir}'.`);
    }
};

/**
 * Initializes an app.
 *
 * Creates these directories needed for an app:
 * .../<userDataDir>/<appName>/
 * .../<userDataDir>/<appName>/logs/
 *
 * After that initializes the logger, loads the app and returns it.
 *
 * @param {string} appDir the directory of the app to load.
 * @returns {Promise<object>} Resolving to the loaded app.
 */
export default async appDir => {
    const appBaseName = path.basename(appDir);
    const userDataDir = getUserDataDir();
    const appDataDir = path.join(userDataDir, appBaseName);
    const appLogDir = path.join(appDataDir, 'logs');
    setAppDirs(appDir, appDataDir, appLogDir);

    await ensureDirExists(appDataDir);
    await ensureDirExists(appLogDir);

    logger.addFileTransport(getAppLogDir());
    return loadApp(appDir);
};
